Telephone-exchange system.



S. B. WILLIAMS, 1R.

TELEPHONE EXCHANGE SYSTEM.

APPLICATIAGN man JULY 14. 1917.

Patented Sept. 24, 1918.

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APPLICATION FILED JULY I4. 1917.

Patented Sept. 24, 1918.

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UNITED sTATEs PATENT oEEicE SAMUEL B. WILLIAMS, JR., OF BROOKLYN, NEW YORK, ASSIGNOR TO WESTERN ELEC- TRIO COMPANY, INCORPORATED, YORK.

To all whom it may concern:

Be it known that I, SAMUEL B. WILLIAMS, Jr., a citizen of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented certain new and useful Improvements in Telephone- Exchange Systems, of which the following is a full, clear, concise, and exact description.

. This invention relates to a call distributing system for telephone exchange systems,

and more particularly to a system of this,

ythe calling subscriber in establishing a connection. Y

In accordance with a feature of the invention, a plurality of line finding switches are provided, each having access to a. large number of lines. These lines are arranged in small groups in the finder switches and such finder switches are directed to t-hc particular groupfincluding a calling lineby means of apparatus common to a plurality of such More specifically thc lines are divided into groups of one hundred and a plurality of finder switches are provided having access to said groups. The groups of one hundred lines are connected in subgroups often in thender switches. A pair of distributer switches and a corresponding pair of switches of the type known in the art as line switches, are employed for the purpose of -directing the finder switches to the subgroups including the calling line. By virtue of this arrangement in finding any calling lines it is only necessaryfor the finder switch to hunt in the small subgroup.

In the embodiment of the invention disclosed the distributers are of the typel shown in the applicants pending application, Se-` rial N o. 144.069, renewed JanuaryY 23, 1917. The line switches are of the type shown in thc United States Patent 1.078g685 vto A. E. Keith. i

In the drawings Figures 1 and 2 diagrammaticaliy represent the apparatus individual to a group of one hundred lines and Fig. 3 is a diagram showing the arrange- Specification of Letters Patent.

' the distributer.

OF NEW' YORK, N. Y., A; CORPORATION OF NEW TELEPHONE-EXCHANGE SYSTEM. i

Patented Sept. 24, 1918. Application led July 14, 19.17. Serial No. 180,632. I i i mentor the distributer contacts. There are i Yprovided for each fifty lines, two distributers such as indicatedinig. 3. These distributers are provided with tive groups of ten line contacts, s uch as 16, 17 and 18. There is also provided for each group of ten lines a pair of contacts 19 and 20, and a long contact 21. A rotatable arm 22 carries five brushes 11, 12, 13,14 and 15 Vwhich coperate with these contacts. The armis adapted toy A beV rotated through a pawl and ratchet mechanism from a motor magnet 10 which isf intermittentlyactuated at certain times by an interrnpter.

There are also provided for each group of one hundred lines two line switches A and B, one of which is individual to each disv responding-to the five groups individual to f Whenl the brush 15 of the distributer rests upon the contact 20, provided no call has been registeredin'the4 group over which the brushes have just passsed, a circuit is established for themagnet 24, which in turn closes a circuit for the magnet 75, causing the plunger arms 26 to bepmoved back and forth in front of the stationary terminalsjindicated at 27. Also, if no calls are received in the group of ten lines when the brushes carried by the dis-l tributer arm reach thepair of contacts 19 and 20, individual to the groi'1p,the power magnet 10Vwill be energized over a circuit which rextends from battery through the interrupter,lmag'net 10, brush V14, contact 19,- back contact and outer left-hand armature of the'relay 3, back contact and yleft-hand armature of relay 7 to ground.,` The arm will, therefore, be stepped forward and the brush 14 will be carried into contact with the contact 21, through which a circuit will be maintained for thepower magnet 10 direct to ground, so that the: `arm will continue to step forward until thecontacts 19 and 2OV ot' the next group are'reached and if no call has been initiated during the time that the brushesjll, l2 and 13 are passing over the contacts 16, 17 and 18 individual to that group of ten lines, the arm of the distributer will continue to be stepped forward. As the magnet 24 is energized each time, the brush 15 makes contact with the contact 20 and the arms 26 of the line switch A will be stepped back and forth over the contacts 27. For each group of one hundred lines there is provided a set of trunks or connecting circuits,one of which is shown in Fig. 2, and individual to each of these trunks and having access to the terminals of the group of one hundred lines is an ordinary selector or finder switch of the type known as the up-and-around type. As will more clearly appear from a description of the operation of the system, these finder switches are controlled in their tlirst operation from the line switches and consequently from the distributers. .o

Common to the two line switches and hence to the group of one hundred lines is an interrupter indicated in general at 29, which consists of a constantly driven shaft 90, which carries a series of ten interrupters Nos. 1 to 10, and a pick-up interrupter which, for the sake ot' convenience is shown on Fig. 2 and is indicated at 108. Inasmuch as the arms 26 of both line switches reverse their direction for each complete revolution ot' the corresponding distributer, and inasmuch as the particular set of contacts 27 which are operated by said arms 26 as will presently be described, determines which of the interrupters shall be made operative to control the setting of the linder switch, means are provided to automatically change the interrupter connections when the line switches change their direction of motion. This is done by means of the relays 30, 31, 30a and 31a. The relays 30 and 31 are adapted to be operated by means of a pair of contacts 32, which in turn is controlled by a cam 33 on the line switch, the arrangement being such that for one half revolution of cam 33 while the arms 26 are being movedV in one direction, the contacts 32 are closed, while for the other half revolution, the contacts 32 are open. By virtue of this arrangement, if the plunger arm 26 is, for example, plunged into the first set of contacts 27, either the No. 6 or No. 10 interrupter is connected to the impulse lead 34, depending upon whether the relay 31 is energized or not. There is also provided individual to each group of fifty lines and each distributer and line switch, a set of relays indicated at 3, 4, 5 and 6, a similar set of relays for the line switch B being indicated at 3b, 4b, 5b and 6h. It is thought that the general arrangement of the apparatus has been suiiiciently described so that the general operation of the system which will now be described may be understood.

For purposes of illust-ration. it will be assumed that the subscribers line shown in Fig. 1 is a line in the sixth subgroup often of a group of one hundred lines; therefore,

the terminals of this line are connected in the sixth level of all of the finder switches having access to that group of one hundred lines. Also the terminals of this line appear in the first group of ten in the distributer.

As long as there are no calls initiated in the group of fifty lines apportioned to the distributer shown the operation is as follows: The arm 22 of the distributer is continuously rotated by the power magnet 10, which magnet is alternately energized in the following circuits: from battery, through the interrupter, magnet 10, brush 14, contact 2l (Fig. 3) to ground, or from battery through the interrupter, magnet 10, brush 14, contact 19, contact and outer left-hand armature of relay 3, back Contact and lefthand armature of relay 7 to ground. Each time the brush 15 makes contact with the contact 20, which occurs five times per revolution of the distributer, the following circuit is established from battery, magnet 24, arm 37, contact 23, contact 20, brush 15, contact and outer right-hand armature of relay 3, back contact and outer left-hand armature of relay 6 to ground. The relay 38 is energized in parallel with the magnet 24 in this circuit and at its arma-ture `and contact connects a ground to the circuit through the contact 40 and arm 39, thus insuring the complete operation of magnet 24. The magnet 24 releases the sector 42 vand closes the contacts 41, establishing a. circuit from battery, magnet 75, contacts 45, contacts 41 .to ground. The magnet 75, when operated in this circuit, opens the contacts 45 and steps the ratchet wheel 43 one step. It-is thought that it will now be apparent that as long as no calls are initiated the arms of the line switch will be moved back and forth, completing a cycle of movement for each two revolutions of the corresponding distributer.

As the distributer rotates the brush 13 makes contact with the sleeve contacts .18 of the lines, and consequently the relay 2 is energized over the following circuit from battery, relay 2, brush 13, contact 18, resistance 35 to ground, provided the par ticular line is not in use. If the line is in use as will presently appear, the relay 2 will not operate, as such relay will be shunted by the low resistance 136 of the finder switch utilized in establishing the connection to such line. It being assumed that a call is initiated on the line shown in Fig. 1 when the brush 14 of the distributer reaches the contact 21 indii-idual to the particular group including the calling line. the distributer arm continues to he. rotated until the brushes 12. 13 and 14 reach the set of contacts 16, 17 and 1S individual to the battery through the relay 2, brush-13, conV tact 18, resistance 35 to ground. The energi zation of the relay 2 connects the relay 1 to the brushes 11 and 12, and since the brushes 11 and 12- are in contact with the contacts 16 and 17 individual to the calling line, the relay 1 will be energized over the subscribers line circuit which is at this time closed at the switch hook at the callingsubscribers station. The energization of the line relay l is only momentary. It should be remembered, however, that, as the callin line is included in the sixth subgroup 0T one hundred lines, before the brush 14 makes contact with the segment 21 of the sixth group, in passing over the contact 20 of the preceding group, in the case as sumed, the tenth group, the line switch arms 26 were moved tothe position shown in front of the irst group of contacts 27, or in other words in front of the group of contacts 27 which are connected to the N o. 6 interrupter, as the springs 32 are maintained open, when the line switch arms are moved in the direction assumed.

The line relay 1 when energized closes a circuit for therelay 3 which extends from battery throu h relay 3 to the armature and contact of re ay 1. The relay 3 closes at its inner left-hand armature a locking circuit for itself through the back contact of the relay 4. At its outer left-hand armature, the relay 3 disconnects ground from the contact 19 and therefore when the brushes 14 and 15 reach the contacts 19 and 20 at the end of the group, no circuit will be found for the power magnet 10, and the distributer arni will be stopped. This being the case, any other calls initiated in the same group of fifty lines ywill be without effect and cannot interfere with ,the call which is being established. At its outer right-hand armature the relay 3 disconnects ground from thebrush 15 so that there will be no circuit for the magnet 24 of the line switch and so that the line switch will also stop. At its inner-right-hand armature, the relay 3 closes a circuit for the relay 5 and 6 in series, which circuit extends from grounded battery through the' left-hand armature and Contact of relay 8, right-hand armature and contact of the relay 7, normal contacts of the relay 6, left-handA wind- Y ing of the relay 5, inner right-hand armature and contact of relay 3 to ground. The relay 5 at its right-hand armature closes a temporary locking circuit for itself independent of the relay 3 and at its left-hand armature closes a circuit for the relay 4, which being energized opens the locking circuit for the relay 3. The relay 6 in operating through its armatures and contacts closes a locking circuit for itself independent of the relayy5, through the relay 7 and opening its normal left-hand contact releases the relay 5. Therefore, the relays 3, 4, 5 and 6 operate in quick succession and all but the relay 6 are almost. im-l mediately released. The locking circuit for relay 6 extends from battery, left-hand armature and contact of relay 8, relay 7, right-hand armature and front contact of relay 6, relay 6, front contact and left-hand armature of relay 6 to ground. The relay 7 opens at its right-.hand armature the original energizing circuit for for the relay 6b. 4 A

As soon 'asthe relay 6 is operated, and consequently the relay 7, a circuit is closed he relay 6 and also for the relay 100. This circuit extends from battery, Vthrough the relay 100, contact 1.09 thereof, side-switch arm 110` in position 1, s1desw1tch arm 111 in position 1, back contact and inner armature of the magnet 106,

conductor 112, front contact and left-hand armature of relay 7, to ground. .The relay 100 at its inner right-hand armature andA Contact closes a locking circuit for itself which extendsv from battery, through the relay 100, contact 109 and inner right-hand armature of relay 100, side-switch arm 113 in position 1,4right-hand armature and contact of relay 101, to ground. At its middle right-hand armature and contact the relay 100 closes a circuit for thep-ick-up relay 102, which circuit is closed through pick-up interrupter 108 just before the interrupter .shaft reaches a position, in which the lfirst conducting segments of the other interrupters carried by f such shaft 90 become operative. When this occurs the pickup relay 102 is operated from a circuit which extends from ground, through the pick-up interrupter 108, middle right-hand armature and contact' of relay 100, normal contact of relay 102, winding of relay 102 to grounded battery. As soon as-the relay 102 is thus operated, the impulse circuit from the interrupter to the vertical magnet 104 of the finder switch individual to the connecting circuit allotted for use is established. This operation of the pick-up relay, however, may

take place simultaneously with the operation of the plunger magnet 9 but cannot take place before the actuation of the plunger magnet because such plunger magnet is actuated over a circuit .closed at the outer lefthand varmature and contact of relay 100. This circuit extends from battery, through the plunger magnet 9. conductor 114, outer left-hand armature and contact of relay 100, conductor 115, the outer left-hand armature and front contact" of the relay 6 to ground. The actuation of the plunger magnet 9 operates the contacts 27, which in the case assumedconnects the No. 6 interrupter in the following circuit: from battery, through the vertical magnet 104, slow release relay 103,

.six times, followed by a longer interruption as ,the interrupter revolves. Upon the first establishment of this circuit, the relay 103 being actuated, a circuit is closed for the side-switch magnet 105, which circuit extends from battery, through magnet 105, sideswitch arm 118 in position 1, contact andwarmature of the relay 103to ground. The side switch, however, is arranged to stop only on release of the side-switch magnet. For each break of the circuit just traced for vertical magnet 104 and the relay 103, the vertical magnet 104 is denergized but the relay 103 will remain energized. The brush shaft is, therefore, stepped up to the sixth level, in whichlevel, in the case assumed, the desired line isf to be found. After the sixth operation of the stepping magnet 104:, the circuit is opened at the interrupter sufficiently long to permit the slow release relay 103 to release, thus opening the circuit of the side-switch magnet 105, and causing the side switch to move into position 2.

Before proceeding further with the effect on the finder switch of the movement of the side switch into position 2, the effect of this operation in releasing the apparatus previously used in directing the finder switch to the sixth level will be described. When the side-switch arm 113 moves into position 2, the locking circuit for both the relays 100 and 102 is opened at the side-switch arm 113, causing both of these relays to release. The release of the relay 100 releases the plunger magnet 9, and as the line switch A has not been moved, the plunger 26 will immediately re'engage the shaft of the line switch. As soon as the finder switch made the first vertical step, the off-normal contact 119 was closed, so that when the relay 100 releases, the following circuit is established: from grounded battery, through the relay 8, conductor 121. arm 120. outer right-hand armature and contact of relay 100, off-normalV contact 119 to ground. The energization of the relay 3 in this circuit. opens the holding circuits for the relays 6 and 7 and restores them to normal. As soon as the relay 7 is released. it being remembered that the arm 22 stopped with the brush 11 on the contact 19,

due tothe energization of the relay 3, and

was prevented from leaving such contact when the relay 3 released, due to the energization of the relay 7 with both the relay 3 and the relay 7 released, a circuit is estab lished for the magnet 10 Vof thedistributer, which extends from battery, through the interrupter, motor magnet 10, brush 14, contact 19, outer left-hand armature and back contact of the relay 3, back contact and lefthand armature of the relay 7 ,v to ground. Therefore, the distributer again starts in motion and continues in motion and drives the line switch A. until another call is initiated. y

Immediately the relay 7 is released, due to the operation of the relay 8, the relay 8 at its right-hand armature establishes the following circuit for the motor magnet 106 of the allotter: from battery, through-the `35 magnet 106, conductor 122,. contact and right-hand armature of the relay 8, conductor 121, arm 120, outer right-hand armature and contact of the relay 100, off-normal contact 119 of the finder switch, to ground; The relay 106 energized in this circuit closes a circuit for the power magnet 107 of the allotter, which extends from battery, through the interrupter, power magnet 107, outer armature and contact of the relay 106, to ground. At its inner armature the relay 106 disconnects the conductor 112 from the allotter brush 111, in order Ato prevent the operation of the relays such as 100 associated with all the nder switches, in case a call should come in on the particular group of fifty or any call lines terminatin at the distributer shown. The relay 106 will be maintained energized as long as the arm 120 passes over contacts individual to the finder switches which are in use, as the olf-normal spring, such as 119 of all such nder switches will be operated to connect a ground to the corresponding allotter contacts. As soon as an idle finder switch is found,.how 110 ever, the relay 106 will release and open the circuit of the motor magnet 107 of the allotter, thus allotting the next idle finder switch for use in connection with the next call initiated in either of the two groups of 115 fifty lines. With the side switch in position 2, a cireuit is closed for the rotary magnety 123 of the finder switch. This circuit extends from the interrupter, through the rotary magnet 120 123, side-switch arm 124k in position 2,v left-v hand armature and back contact of the relay 125, to ground. Also when the sideswitch arm reaches position 2, a circuit is established for the sideswitch magnet 105, 125 which extends from battery, side-switch arm 11S in position 2, back contact and armature of the test relay 126, to ground. Further.- more, in posit-ion 2 of the side switch, a circuit is prepared for the relay 127,'side- 130 switch arm 128 in position 2, and through the brush 129. As the rotary magnetof the selector switch operates, the brushes 129, 130 and 131 are moved over the stationary terminals 132, 133 and 134'. When the stationary terminals 134, individual to the lines, are encountered provided such lines are not connected to by other finder switches. the relay 127 is energized over a circuit which extends from battery, the relay 127, side-switch arm 12S in position 2, brush 129, terminal 134, conductor 36, through the rcsistance 35, to ground. The operation of this relay 127 connects the test relay 126 across the brushes 130, 131, and hence when the brushes 130, 131 reach the terminals 132, 133 individual to the calling line, the relay 126 is energized over a circuit which extends from battery, through the right-hand winding of relay 126, inner armature and contact of the relay 127, brush 130, terminal 133, out over the subscribers line, and back to the terminal 132, brush 131, outerarmature and Contact of the relay 127, left-hand winding of the relay 126, to ground. The

Y relay 126 when energized opens the energizing circuit for the side-switch magnet 105,

. causing theside switch to step to position 3,

in which position. the circuit ofthe rotary magnet 123 is opened, and the finder switch is stopped with the brushes thereof in connection with the calling line. Y

As soon as connection is established with the calling line the supervisory relay is included incircuit, with the battery 137 and the transmitter of the calling line. AThe relay 135 operates the slow release relay 101 over a circuit from battery, relay 101, contact and armature of relay 135 to ground. The Vrelay 101 at its right-hand armature disables the release magnet 125 and at its left-hand armature connects the low re-v sistance 136 to the sleeve or third conductor of the line, thus preventing the operation of the relay 2 of the distributor and thev relay 127 of other finders when they are connected to the terminals of such line in such distributer and iinder switches. A

Upon the termination of conversation, when the calling subscriber hangs up, the relay 135 is denergized, and consequently the relay 101 is released. The relay 101 when released, with the side switch in position 3, closes a circuit from battery, through the release magnet 125,v side-switch arm 113 in position 3, right-hand armature and contact of the relay 101, to ground. The operation of the release magnet restores the,

invent-ion disclosed will be suiiiciently understood.

What is claimed is:

1. In a telephone exchange system, lines divided into main groups and subgroups, line finder switches having access to a plurality of main groups, means individual to each main group for successively testing all of the lines in a main group Jfor calling lines, means responsive-to a vcondition indicating'a calling line for identifying the sub*V group including such line, and means controlled by such identifying means for directing a finder switch to such identified subgroup and starting such finder switch to hunt in said subgroup for such calling line.

2. In a telephone exchange system', lines arranged in main groups and subgroups, `a plurality ofvnder switches each having access to a plurality of main groups, means individual toA a lmain group foritesting the lines of such-main group in succession for 'calling lines, means responsive to a condiously testing the lines of said main group for calling lines, means responsive to a condition indicating a calling line to temporarily stop said testing means to identify the subgroup containingsuch calling line, means 4controlled from such testing means in Yaccordance Awith the position in which such testing means -is stoppedfor directing a finder switch -to the terminals of the subgroup including the calling line, and means for starting said inder switch to hunt in the subgroup for the calling line and for simul taneously causing said testing means to resume its testing operation.

4. AIn a telephone exchange system comprising lines divided into groups and subgroups, line finder switches having access to.

said main groups, motor magnets individual to said line finders adapted to respond to impulses to direct said line finders to the subgroups, a plurality of impulse senders, means independent of said line finders for testing the lines of a main group in succession, and means controlled from Ysaid testing means for selectively associating the Y motor magnet of one of said line finders with one of such plurality of impulse senders to direct said line finder to a subgroup.

Vrality of said main groups,

ing device in synchronism therewith, means for stopping testing device is stopped, -a set of impulse means controlled by said senders, and switching device for connecting one of such set of impulse senders to the motormagnet of a line finder to direct said line finderv t0. a subgroup containing the calling line.

switches having access toa plurality of said main groups,- inders, a testing ing all of switching ing device including a plurality device controlled fromv .si'ich'A testof .plunger arms and sets of stationary contact's,a plurality of impulse senders, each. arranged to send a different series of impulses associated with said sets of stationary contacts, means controlled by the movement of the testing device in the testing operation thereof for moving said plunger arms back and forth in front of the sets of stationary contacts,` and means rendered operative when said testing,l device encounters a calling liner in the mainv group to operate one of such plungers to cause it to operate one of the sets of contacts, and means controlled by the operated set of contacts for directing a line finder switch to the subgroup containing the calling line.

7. In a telephone exchange system, lines divided into main groups and subgroups, line finder switches having access to a plu- .i testing device adapted to continuously and successivelyI test the lines of a main group for calling lines, a line switch associated with said testing device, said line switch including a plurality of plungers and sets of contacts, there being a p unger on such line switch for each line nder having access to the same main group of lines and a set of contacts for each sub-group of lines, means controlled by said testing device for moving said plungers back said switching device when said 1 groups "of, ten, line y vaccess to two main groups, a testing device y, a .main group and a 6. In a telephone exchange system, lines divided into main and subgroups, line'nder.;

" from the testing cline switch to move the plungers thereof Iback and forth over sets of stationary conmotor magnets vfor `such linev device for successively test'fzl the lines-'of the main group, an

and forth in front of lsuoli sets of stationary V contacts, impulse senders associated with said sets of contacts, means controlled from I said testing device when a calling line is encountered to cause a plunger of said line switch to operate a set of stationary contacts individual to the subgroup containing the' calling line, andmeans controlled throughl l the operated set of contacts to connect lan im-Y pulse sender adapted to send the proper p number of impulses to direct the'line nder individual 'to the plunger to thev subgroup containing the calling line. t

8. In a telephone exchange system, lines dividedinto'main groups of fifty and 'subfinder switches: having adapted to successively test the fifty lines of line switch provided with -a plunger for eacli line finder having access to the main group, means controlled device for operating said tacts, there being a set of such contacts for each group of ten lines of the main group Vof fifty to which the line switch is individual, an interrupter associated with each set, of contacts, means included in said testing -device'responsive to a condition-on a line indicating that such line is calling for stopping said line switch and operating one of said' plungers, means operated by said plunger for connecting one of said interrupters with the motor magnet of a line finder to direct said line finder to the subgroup containing the calling line. y

9. In a telephone exchangel system, lines `divided into main groups and subgroups, a

necting'means associated therewith under the control of the testing means, and means individual to the subgroups identified by such testing means for directing such connecting means to such subgroup.

'In witness whereof, I hereunto subscribe my name this 13th day of July, A. D. 1917.

SAMUEL B. WILLIAMS, Ja 

